PHOENIX -- It's was hard to determine which took longer Saturday night at Chase Field -- Paul Maholm's trot around the bases on his two-run homer in the fourth inning, or the Diamondback's 6-run rally off Maholm in the bottom of the inning.

Either way, Arizona wound up with a 10-5 win over the Cubs before 38,542 -- the second biggest crowd of the season at Chase.

"A word you can print is 'frustrating,'" Maholm said.

After winning the first two games of the White Sox series, the Cubs are back to their old ways with three straight losses.

They're now 9-27 since May 15 -- a .250 winning percentage -- leaving them with the worst record in major league baseball. The Cubs also reached their low water mark of the year at 23 games under .500 (24-47) and are on pace to lose a franchise-record 107 games.

After his 2nd career home run momentarily gave the Cubs a 2-1 lead over the Diamonbacks, Maholm quickly gave it up, and was yanked by manager Dale Sveum before getting out of the fourth.

Sveum said it's been a recurring theme for Cubs pitchers after they get a hit in the inning.

"We were just talking about how that seems to be our Achilles heel, whenever one of our pitchers gets a hit or does something like that," he said. "The next inning ain't too good."

Maholm said it had nothing to do with his home run.

So what happened?

"You watched it," he said. "I didn't make pitches. I made a pitch that I thought I was getting out of it. Didn't make any pitches after it."

Maholm was referring to a throwing error by third baseman Luis Valbuena that preceded four straight hits, including a two-run triple by Paul Goldschmidt.

"You make a pitch you think you're getting out of it, and all hell broke loose," he said.

Maholm was charged with six earned runs on nine hits and three walks over 3 1/3 innings, lifting his earned-run average from 4.88 to 5.38. He hasn't won since May 9, going 0-4 with four no-decisions over his last eight starts.

The Cubs pounded out 14 hits off Diamondbacks pitching, but went 2-for-11 with runners in scoring position and stranded 10 base-runners, one night after leaving 11 men on base. Sveum pointed to LaHair, the No. 3 hitter, who went 0-for-5 with runners on base in every at-bat. He came in hitting .159 with runners in scoring position.

"Our core guys have got to start doing something in the middle of the order," Sveum said.

Asked if he could move LaHair in the order, Sveum said he had to "give him a chance," adding: "We have to change the approach or whatever's going on."

David DeJesus had a four-hit game for the 10th time in his career, while Starlin Castro had his eighth career four-hit game. Yet eight hits from the Nos. 1 and 2 hitters in the lineup were rendered meaningless thanks to the lack of clutch hitting and the poor outing by Maholm (4-6).

Justin Upton's solo homer in the third gave the D'Backs an early lead, while the Cubs stranded five base-runners over the first three innings. Maholm's long homer to right off starter Ian Kennedy put the Cubs on top before Arizona rallied for six runs on five hits, a walk and the error.

The Cubs scored three in the fifth to knock Kennedy out of the game, pulling to within two runs at 7-5. But reliever Scott Maine served up a home run to Goldschmidt in the sixth and gave up another run in the seventh as Arizona pulled away.

"Overall as a staff we have to make better pitches, and we've got to make plays and swing the bat and do a lot of things better," Maholm said. "They're on a roll at home, and we're not playing very well on the road."